No service only on Tmobile

[Jan Lachut]

Hi there, I having really strange problem with my NL 920, no service with T-Mobile but LTE with AT&T.
About 3 weeks ago I bought used NL 920 locked for att from ebay, I found a web that offer unlocking code for $49.99 ( don't know if that a fair price for unlocking code ), meantime before unlocking phone I download GDR3 update. Yesterday I received unlocking code and I was so happy that I could finally use my new phone ( current HTC 8X from Verizon ). Right after I entered code using tmobile SIM card I wait like few minutes to find network but nothing " no service ). I did hard reset, playing with ##3282# and still couldn't connect the right network. The strangething is I have no problem to find any networks like tmobile, ATT or even Verizon, but I can't to connect to any of them.
But the weirdest think is when I insert AT&T SIM card works fine. Also I notice weird message "Phone not allowed MM#6 " and two X in a circle ( on a bottom of ##3282# settings )

 

[Laura Knotek]

According to this thread on CrackBerry, that error message means the device was reported lost or stolen by its original owner. Phone Not Allowed MM6 / Sim Card Rejected / SOS - BlackBerry Forums at CrackBerry.com

 

[Jan Lachut]

If that so, then tell me why AT&T SIM card working with no problem on ATT device? If owner report phone as a lost/stolen i shouldn't be allow to making any calls using ATT SIM card. What T-Mobile have to do with this?

 

[palandri]

I am not sure your phone is unlocked. What happens if you try dialing ##782# - not sure if this code works on a 920.

Update: ##782# only works on early WP's, it won't work on a 920.

Here's something else to try: http://www.t-mobile.com/verifyIMEI.aspx

In searching MM#6, it appears there's multiple reason for that code, one of course being blacklisted. When you buy a used phone it's sometimes hard to tell if someone tried to flash the ROM or make other modifications.